Apple tree named &#39;WA 38&#39;

ABSTRACT

A new and distinctive variety of a  Malus domestica  apple tree, named ‘WA 38’ that is distinguished by its intense and nearly full color, internal indices that are different than its parents, and its long common storage life.

LATIN NAME OF THE GENUS AND SPECIES OF THE CLAIMED PLANT

Botanical/commercial classification: Malus domestica/apple tree.

VARIETAL DENOMINATION

‘WA 38’.

BACKGROUND OF THE INVENTION

The invention refers to a new plant variety of apple tree (Malus domestica) named ‘WA 38’. This new variety is distinguished by its intense and nearly full color, internal indices that are different than its parents, and its long common storage life.

‘WA 38’ originated from a cross of ‘Enterprise’ and ‘Honeycrisp’ in Year 1. The germinated seedling was grown in a greenhouse at Wenatchee, Wash. In September of Year 2, ‘WA 38’ was chip budded onto ‘M9’ rootstock and the resulting tree was planted in the evaluation orchard at Douglas County, Wash. in the spring of Year 5. Fruit from this originally budded tree were observed in Year 7 and Year 8 and second generation trees were made by chip budding onto M9 rootstock in the fall of Year 8. Second generation trees were planted at three locations in Washington State near Chelan, Douglas County, Wash.; near East Wenatchee, Douglas County, Wash.; and near Basin City, Franklin County, Wash. Fruit from second generation trees were observed and compared to that of the originally budded tree in Year 12, Year 13, Year 14, and Year 15 and found to be essentially similar to that of the originally budded tree.

SUMMARY OF THE INVENTION

The ‘WA 38’ apple tree variety exhibits exceptionally long storage life in common storage. ‘WA 38’ loses little of its crispness, sugar, and acid following five months of storage, whereas that of its parents declines considerably. The appearance of ‘WA 38’ fruit is nearly full color and has an intensity that is unique among other apple varieties of the same season. Like both its parents (i.e., ‘Enterprise’ and ‘Honeycrisp’), ‘WA 38’ is heterozygous for , the ASC1 gene and homozygous for the ACO1 gene, both of which are involved in ethylene production. These genes confer low ethylene production, which in turn affects storage life. The ACS1 and ACO1 genotypes were determined using the method described in Zhu and Barrit (2008). The harvest maturity date of ‘WA 38’ is approximately five weeks later than that of the parental variety ‘Honeycrisp’, and approximately 5 days earlier than that of the parental variety ‘Enterprise’. Additionally, fruit appearance and internal indicies are distinctly different than that of the parental varieties ‘Honeycrisp’ and ‘Enterprise’.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1. View of the dormant stage of ‘WA 38’ originally budded tree.

FIG. 2. View of blossoms from the originally budded tree of ‘WA 38’.

FIG. 3. View of typical ‘WA 38’ originally budded tree fruit at harvest maturity.

FIG. 4. View comparing harvest mature fruit of ‘WA 38’ (top row), and its parents ‘Enterprise’ (center row), and ‘Honeycrisp’ (bottom row).

DETAILED BOTANICAL DESCRIPTION

The following detailed description, except for description of fruit, is from the ‘WA 38’ originally budded tree grown at Orondo, Douglas County, Wash. The ‘WA 38’ tree was 11 years old when measurements were taken. The USDA hardiness zone 6b. All color references are from the RHS colour chart by the Royal Horticultural Society.

-   Tree:     -   -   Type.—spreading; moderately heavy spur development, and             precocious with spur development beginning on two-year old             wood.         -   Vigor.—considered moderate on the low side with the current             season's growth ranging from 26.0 cm to 50.2 cm with an             average of 37.0 cm.         -   Overall shape.—upright and spreading.         -   Height.—16 feet.         -   Width.—14 feet.         -   Hardiness.—considered hardy for the regions grown in; USDA             hardiness zone 6b.         -   Productivity.—considered high. -   Trunk:     -   -   Size.—diameter at a height of 30cm above graft union is 10.3             cm.         -   Bark texture.—considered smooth for 11 year old tree.         -   Bark color.—from the greyed-orange group (RHS 199A).         -   Lenticels.—present and moderate in number averaging 6             lenticels per 9 cm²; shape is elongated and oriented             horizontally; average width is 1.7 mm; average length is             10.9 mm.         -   Lenticels color.—from the brown group (RHS N200A). -   Branches:     -   -   First year branches.—Diameter: at mid-point of growth ranges             from 3.7 mm to 5.0 mm and averages 4.5 mm Length: current             season's growth ranges from 26.0 cm to 50.2 cm with an             average of 37.0 cm. Bark color: from the greyed-orange group             (RHS 176A) Lenticels: are numerous averaging 17 lenticels in             a 1 cm section of branch; shape is mostly round with a few             oval in shape; oriented vertically; diameter ranges from 0.4             mm to 0.9 mm; oval dimensions range from 1.4 mm to 1.6 mm in             length and 0.7 mm in width; and color is from the             green-white group (RHS 157D).         -   Scaffold branches.—Size: ranges from 4.2 cm to 7.9 cm in             diameter with an average of 5.9 cm as measured 10 cm from             the trunk Angle: as trained is moderately flat to near flat,             ranging from 75 to 85 degrees from vertical Branch color:             from the grey-brown group (RHS 199A) Lenticels: few in             number, averaging 11 lenticels per 9 cm²; shape and size is             variable, mostly elongated, with some round; length ranges             from 8.4 mm to 18.9 mm and width ranges from 1.0 mm to 1.7             mm; round diameter ranges from 1.0 mm to 1.3 mm; orientation             is horizontal; and color is from the greyed-orange group             (RHS 166D). -   Leaves:     -   -   Shape.—considered broadly acute on the round side and is             upward folding.         -   Texture.—upper surface is leathery with some puckering;             lower surface is smooth with some puckering.         -   Sheen.—upper surface has a high sheen.         -   Pubescence.—present on lower surface only covering 100% and             is moderately heavy; color of lower surface pubescence is             from the greyed-yellow group (RHS 160D); light covering of             white pubescence (RHS 155E) is found along veins of upper             surface.         -   Length.—blade length ranges from 7.2 cm to 8.9 cm with an             average of 8.1 cm.         -   Width.—ranges 5.2 cm to 6.3 cm with an average of 5.7 cm.         -   Margin.—serrate with a few bi-serrate regions.         -   Tip.—acuminate.         -   Base.—rounded.         -   Stipules.—present on most petioles; 0 to 2 present with most             being 1; shape is acicula; length ranges from 2.0 mm to 6.3             mm with an average of 4.4 mm; width at base ranges from 1.0             mm to 1.6 mm with an average 1.3 mm; color of upper and             lower surface is from yellow-green group (RHS 1146D); and             pubescence is present on both upper and lower surfaces,             considered fine with 100% coverage over both surfaces;             pubescence color is from the greyed-yellow group (RHS 160D).         -   Leaf blade color.—upper surface is from the yellow-green             group (RHS 147A); lower surface is from the yellow-green             group (RHS 147C).         -   Mid-vein.—prominent with considerable fine pubescence on             under surface of vein; width at mid blade ranges from 1.1 mm             to 1.6 mm with an average 1.4 mm; upper surface color is             from the yellow-green group (RHS 147A); lower surface color             is from yellow-green group (RHS 147C); pubescence covering             100% of the lower surface is from greyed-yellow group (RHS             160D).         -   Petiole.—length ranges from 24.5 mm to 35.9 mm with an             average of 30.1 mm; shallow groove runs the entire length of             the upper surface; diameter at mid point ranges from 1.4 mm             to 1.9 mm with an average of 1.7 mm; color of upper surface             is from the yellow-green group (RHS 145C); color of lower             surface is from the yellow-green group (RHS 145D);             pubescence is abundant and fine over the entire length and             circumference of the petiole; color of pubescence is from             the greyed-yellow group (RHS 160D).         -   Buds.—usually on single spurs; shape is considered acute             with base being truncate with spur; diameter ranges from 4.1             mm to 4.9 mm with an average of 4.4 mm; length ranges from             6.6 mm to 10.2 mm with an average of 8.3 mm; bud scale color             from the purple group (RHS N77A) -   Flowers: full bloom date May 1 at Orondo, Douglas County, Wash.;     number of blossoms per bud ranges from 4 to 6 with an average of 6;     fragrance is apple-blossom like.     -   -   Size.—considered large, when fully expanded the diameter             ranged from 51.6 mm to 57.5 mm with an average of 53.9 mm.         -   Petal.—width ranges from 18.0 mm to 21.1 mm with an average             19.2 mm; length ranges from 24.4 mm to 27.3 mm with an             average 25.2 mm; shape is elliptic; typical petal number is             five; petal margins are smooth, both tip and base of petal             are rounded; petal surface is slightly glabrous.         -   Color.—both upper and lower surfaces are white (RHS 155E);             where exposed prior to opening, lower surface has highlights             from red-purple group. (RHS 64B)         -   Stamen.—number ranges from 18 to 21 with an average of 21;             filament length ranges from 5.5 mm to 11.2 mm with an             average of 8.5 mm; filament color is from the white group             (RHS 155C); anthers are kidney shaped with an average size             of 1.6 mm wide×2.7 mm long; mature anther color is from the             yellow group (RHS 10D).         -   Pistil.—typically five pistils per flower; length ranges             from 14.7 mm to 19.7 mm with an average of 17.2 mm Styles:             five in number, fused at ⅓ distance from basal end with the             fused region covered in white (RHS 155E) pubescence; color             is from the yellow-green group (RHS 145B) Stigma: round club             shaped 0.6 to 0.7 mm in diameter; color is from the             yellow-green group (RHS 153B).         -   Sepals.—five per blossom; shape is considered thin deltoid             with the tip being acuminate and the base being truncate;             length ranges from 13.2 mm to 8.8 mm with an average of 11.9             mm; width ranges from 3.8 mm to 4.4 mm with an average of             4.1 mm; abundant white (RHS 155E) pubescence is present on             both upper and lower surfaces; upper surface color is from             the yellow-green group (RHS 146C); lower surface color is             from the yellow-green group (RHS 148D); both upper and lower             tip surfaces highlight color from the red-purple group (RHS             64B).         -   Peduncle.—length ranges from 16.1 mm to 23.0 mm with an             average of 19.5 mm; color is from the yellow-green group             (RHS 146B); considerable white downiness (RHS 155E) present             over the entire surface.         -   Pollen.—moderate amounts of pollen are produced, with color             from yellow group (RHS 10D). -   Fruit: observations and testing from 1^(st) generation tree fruit     grown at East Wenatchee, Douglas County, Wash.; production is     moderate to heavy, falling within the range of existing commercial     cultivars.     -   -   Form.—considered uniform round-conical; regular, uniform and             exhibits lopsidedness.         -   Size.—considered medium large with a normal crop level;             equatorial diameter ranges from 80.0 mm to 88.3 mm with an             average of 83.9 mm; axis diameter ranges from 76.4 mm to             85.6 mm with an average of 79.0 mm; typical weight ranges             from 254 g to 332 g with an average of 281 g.         -   Stem.—considered long and medium thick; length ranges from             22.3 mm to 29.5 mm and averages 25.7 mm; diameter ranges             from 1.8 mm to 2.8 mm with an average of 2.3 mm; color from             the yellow-green group (RHS 146B).         -   Stem cavity.—width ranges from 28.3 mm to 36.1 mm with an             average 32.6 mm; depth ranges from 20.9 mm to 23.9 mm with             an average of 22.7 mm; occasional light russet over bottom ⅓             of cavity; cavity shape is acuminate; stem cavity is not             lipped.         -   Basin cavity.—considered abrupt; surface is wavy; puckered             around eye; light ribbing; white downy hairs at base from             the white group (RHS 157D); width ranges from 25.9 mm to             31.5 mm with an average of 28.8 mm; depth ranges from 11.6             mm to 18.4 mm with an average of 13.8 mm.         -   Eye.—erect convergent; sepal color is from the yellow-green             group (RHS 148C); sepals contain white downy hairs from the             white group (RHS 157D).         -   Skin.—texture is considered tender; thickness is considered             thin; appearance is considered more streaked than marbled             with scant bloom present; skin color of over streak is from             the greyed-purple group (RHS 183B); skin color of under             streak is from the greyed-purple (RHS 183D); skin under             color is from the red group (RHS 48A); skin lenticels are             numerous, small, round, smooth with the skin; skin lenticels             are more numerous towards the calyx end averaging 4             lenticels per cm² at stem end, 11 lenticels per cm² at calyx             end; areolar at the stem end; color is from the white group             (RHS 155E) and areolar color is from the red group (RHS             48A); skin lenticel size ranges from 0.2 mm to 0.5mm in             diameter with aerolar diameter ranging from 1.0 mm to 1.5             mm.         -   Core.—core position is considered median; core line position             is basal meeting; core diameter ranges from 38.7 mm to 46.3             mm with an average of 42.9 mm; core length ranges from 28.2             mm to 32.8 mm with an average of 30.5 mm; core shape is flat             conical.         -   Cell (locule or carpel): five per fruit; not tufted; shape             is elliptical; length ranges from 17.1 mm to 23.4 mm with an             average of 19.6 mm; width (axis/edge) ranges from 10.9 mm to             12.8 mm with an average of 11.6 mm; depth (wall/wall) ranges             from 5.7 mm to 7.5 mm with an average of 6.5 mm.         -   Tube.—cone shaped.         -   Stamen position.—median relative to stamens situated             approximately in the middle of the tube (the cavity just             beneath the eye).         -   Cell attachment to axis.—axial and open, meaning cells are             symmetrical and each cell is open.         -   Seed.—number ranges from 1 to 3 with an average of 2; shape             is acute; seed length ranges from 8.3 mm to 9.4 mm with an             average of 9.0 mm; seed width ranges from 4.0 mm to 4.7 mm             with an average of 4.3 mm; seed color is from the brown             group (RHS 200D).         -   Flesh.—crisp, melting, juicy, sub-acid with mild apple like             flavor; color is from the yellow-white group (RHS 158D);             flesh browning very little to none after one hour; quality             is very good.         -   Aroma.—apple like and moderate in intensity.         -   Date of harvest maturity.—typically late September/early             October, observed harvest maturity of current season was             October 5.         -   Genotype.—WA 38’ is heterozygous (1,2) for ACS1 and is             homozygous (2,2) for ACO1.         -   Keeping quality.—excellent; up to five months in common             storage; flesh browns very slightly after being exposed. -   Pollination: any diploid apple of the same bloom season -   Use: for dessert -   Disease and insect resistance: may have some resistance to Venturia     inaequalis (apple scab) from its maternal parent ‘Enterprise’;     otherwise is considered to be susceptible to all insects and     diseases found in the region of Central Washington

Table 1 represents maturity indices of the ‘WA 38’, ‘Honeycrisp’, and ‘Enterprise’ varieties. In Table 1, pressure is a measure of fruit firmness, ° Brix is a measure of soluble solid content of fruit, and titratable acid is a measure of fruit acidity. The ‘WA 38’ and ‘Honeycrisp’ varieties were sampled on two different dates. The mature harvest date of ‘Enterprise’ was October 1, Year 15, and the mature harvest date of ‘Honeycrisp’ was October 9, Year 15.

TABLE 1 Maturity indices Sample Titratable Run Pressure Acid Variety Date (Newtons) °Brix pH (g/100 ml) ‘WA 38’ Oct. 5,  17.3 13.7 3.44 0.62 Year 15 ‘Honeycrisp’ Sep. 10, 14.5 11.1 3.30 0.52 Year 15 ‘Enterprise’ Oct. 10, 19.3 15.7 3.52 1.09 Year 15 ‘WA 38’ Dec. 21, 16.7 13.8 3.58 0.51 Year 15 ‘Honeycrisp’ Oct. 5,  15.2 14.3 4.02 0.30 Year 15

The attached figures show the ‘WA 38’ tree and various aspects of its fruit. FIG. 1 is a photo of the dormant originally budded tree of ‘WA 38’. FIG. 2 is a close up of a blossom cluster from the ‘WA 38’ originally budded apple tree. FIG. 3 depicts ‘WA 38’ apples at harvest maturity on the originally budded tree. FIG. 4 shows the ‘WA 38’ fruit as compared to the fruit of its two parental varieties at harvest maturity. ‘WA 38’ is the top row, ‘Enterprise’ is in the center and ‘Honeycrisp’ is at the bottom. 

What is claimed:
 1. A new and distinct apple tree variety named ‘WA 38’, as herein shown and described. 